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With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia. ©2007 Nature Publishing Group.

EXTECH IV was a multidisciplinary field and laboratory project to enhance and preserve geoscience data and improve exploration methods for unconformity-type U deposits. Regional to detailed research was coordinated at sites across the Basin, focusing on McArthur River. Brief discussion is presented of results implying a new regional basement geology and revised stratigraphy. It is also suggested that faults, basin development and ore deposits are linked, that structurally reworked ore is consistent with multiple ore-forming events, and that paleo-valleys are spatially associated with some Athabasca ore deposits. New software and improved technology have rejuvenated the geophysical and geochemical exploration toolkit for the Basin. Potential sources of organic reductants to precipitate uraninite are discussed along with sources and transport of uranium., EXTECH IV was a multidisciplinary field and laboratory project to enhance and preserve geoscience data and improve exploration methods for unconformity-type U deposits. Regional to detailed research was coordinated at sites across the Basin, focusing on McArthur River. Brief discussion is presented of results implying a new regional basement geology and revised stratigraphy. It is also suggested that faults, basin development and ore deposits are linked, that structurally reworked ore is consistent with multiple ore-forming events, and that paleo-valleys are spatially associated with some Athabasca ore deposits. New software and improved technology have rejuvenated the geophysical and geochemical exploration toolkit for the Basin. Potential sources of organic reductants to precipitate uraninite are discussed along with sources and transport of uranium.

The Canadian uranium industry began in the 1930s with the development of the Port Radium pitchblende deposit along the east shore of Great Bear Lake in the Northwest Territories. The only other confirmed pithchblende occurrences were reported from the north shore of Lake Athabasca, and this part of northern Saskatchewan became the main exploration focus. In late 1947, the ban on private prospecting and staking for uranium was lifted resulting in hundreds of radioactive occurrences being found throughout the Beaverlodge area. A total of 36 deposits were explored and 16 individual deposits achieved some production by the late 1950s. The last producing mine, Eldorado's Beaverlodge operation, ceased operations in mid-1982. Between 1953 and 1983, the cumulative production from the Beaverlodge mining district was 64 800 000 lb U3O8. Geology and mineralogy of the area is discussed along with descriptions of the Ace-Fay-Verna and Gunnar mines., The Canadian uranium industry began in the 1930s with the development of the Port Radium pitchblende deposit along the east shore of Great Bear Lake in the Northwest Territories. The only other confirmed pithchblende occurrences were reported from the north shore of Lake Athabasca, and this part of northern Saskatchewan became the main exploration focus. In late 1947, the ban on private prospecting and staking for uranium was lifted resulting in hundreds of radioactive occurrences being found throughout the Beaverlodge area. A total of 36 deposits were explored and 16 individual deposits achieved some production by the late 1950s. The last producing mine, Eldorado's Beaverlodge operation, ceased operations in mid-1982. Between 1953 and 1983, the cumulative production from the Beaverlodge mining district was 64 800 000 lb U3O8. Geology and mineralogy of the area is discussed along with descriptions of the Ace-Fay-Verna and Gunnar mines.

The Athabasca Basin, Saskatchewan, is the premier host for unconformity-type deposits and has an estimated resource in excess of 373 000 t U. Current production comes from mines at Key Lake, Rabbit Lake and Cluff Lake. These deposits are less than 200 m deep and represent the first generation of unconformity-type uranium deposits. They were discovered by shallow penetrating geophysical methods, surficial geochemical surveys and combined diamond and reverse circulation drilling programmes. The McArthur River and Cigar Lake mines, at depths exceeding 400 m, are scheduled for production by the end of this decade and represent the next generation of high grade deposits. The McArthur River deposit has a combined reserve/resource of 416 500 000 lb U3O8 with an average grade of 14.36% U3O8, whereas the Cigar Lake deposit has a reserve of 353 300 000 lb U3O8 at an average grade of 13.6% U3O8. Exploration programmes are being conducted in similar mid-Proterozoic basins worldwide. The trend towards deeper exploration in the Athabasca Basin, and the evaluation of similar basins, will require improved geochemical and geophysical methods., The Athabasca Basin, Saskatchewan, is the premier host for unconformity-type deposits and has an estimated resource in excess of 373 000 t U. Current production comes from mines at Key Lake, Rabbit Lake and Cluff Lake. These deposits are less than 200 m deep and represent the first generation of unconformity-type uranium deposits. They were discovered by shallow penetrating geophysical methods, surficial geochemical surveys and combined diamond and reverse circulation drilling programmes. The McArthur River and Cigar Lake mines, at depths exceeding 400 m, are scheduled for production by the end of this decade and represent the next generation of high grade deposits. The McArthur River deposit has a combined reserve/resource of 416 500 000 lb U3O8 with an average grade of 14.36% U3O8, whereas the Cigar Lake deposit has a reserve of 353 300 000 lb U3O8 at an average grade of 13.6% U3O8. Exploration programmes are being conducted in similar mid-Proterozoic basins worldwide. The trend towards deeper exploration in the Athabasca Basin, and the evaluation of similar basins, will require improved geochemical and geophysical methods.

Structurally hosted lode gold deposits in the Early Proterozoic Reindeer zone have many attributes in common with Archaean counterparts worldwide. Detailed field relationships at Jolu indicate that the development of shear zones and mineralisation in the Star Lake pluton postdated emplacement of the host footwall granodiorite at 1846 Ma and predated regional metamorphism at 1783 Ma. The best estimate for the timing of gold mineralisation is 1807 Ma and is based on U-Pb dating of titanite in a mafic dyke sample closely related to quartz vein mineralisation. This age is identical to high-grade metamorphism of the Trans-Hudson orogen at deeper crustal levels and, as has been shown for some Archaean lode gold deposits, provides a temporal link between gold mineralisation at high crustal levels and high-grade metamorphism and devolatilisation at depth., Structurally hosted lode gold deposits in the Early Proterozoic Reindeer zone have many attributes in common with Archaean counterparts worldwide. Detailed field relationships at Jolu indicate that the development of shear zones and mineralisation in the Star Lake pluton postdated emplacement of the host footwall granodiorite at 1846 Ma and predated regional metamorphism at 1783 Ma. The best estimate for the timing of gold mineralisation is 1807 Ma and is based on U-Pb dating of titanite in a mafic dyke sample closely related to quartz vein mineralisation. This age is identical to high-grade metamorphism of the Trans-Hudson orogen at deeper crustal levels and, as has been shown for some Archaean lode gold deposits, provides a temporal link between gold mineralisation at high crustal levels and high-grade metamorphism and devolatilisation at depth.